Question

下面的脚本是四列的数据框。我的需要是我想一次取一对值（a1，a2）。列“a3”是这样的，如果您检查一对说（a1，a2），当您跨越数据时，该对的值按升序排列。如果表中存在对的副本，我希望“a4”列值的排列方式与特定（a1，a2）值的升序相对应的“a3”列相同。假设第一个（a1，a2）对（“A”，“D”），该对出现三次，相应的a3值按升序排列。类似地，我希望根据a4值的顺序按升序排列a4值。请检查预期结果。谢谢，请提出建议。

a1 = c("A","B","C","A","B","C","A","C")
a2 = c("D","E","F","D","E","E","D","F")
a3 = c(5,15,12,10,40,35,20,50)
a4 = c(100,160,66,65,130,150,80,49)
a123= data.frame(a1,a2,a3,a4)
library(dplyr)
a123_r <- a123 %>%
group_by(a1, a2) %>%
mutate(a3 = sort(a3)) %>%
ungroup()
a123_r

预期输出

a1 = c("A","B","C","A","B","C","A","C")
a2 = c("D","E","F","D","E","E","D","F")
a3 = c(5,15,12,10,40,35,20,50)
a4 = c(65,130,66,80,160,150,100,49)
a123_r <- data.frame(a1,a2,a3,a4)

Answer 1

为了完整起见，这是使用data.table：

的答案

library(data.table)
cols <- c("a3", "a4")
setDT(a123)[, (cols) := lapply(.SD, sort), by = .(a1, a2), .SDcols = cols][]

   a1 a2 a3  a4
1:  A  D  5  65
2:  B  E 15 130
3:  C  F 12  49
4:  A  D 10  80
5:  B  E 40 160
6:  C  E 35 150
7:  A  D 20 100
8:  C  F 50  66

数据

a1 = c("A","B","C","A","B","C","A","C")
a2 = c("D","E","F","D","E","E","D","F")
a3 = c(5,15,12,10,40,35,20,50)
a4 = c(100,160,66,65,130,150,80,49)
a123= data.frame(a1,a2,a3,a4)

在R中按升序对列的值进行排序

1 个答案:

数据